The invention relates generally to metal recycling, electricity production and fuel production and more particularly has reference to a system that uses heat produced by incineration of waste materials to generate sufficient electrical power to refine the metals present in scrapped automobiles to a sufficient purity as to be marketable as either ingots or finished metal products.
A number of methods are currently available to process obsolete scrap. The easiest and most popular method is open burning. However, most obsolete scrap includes a variety of combustible materials such as plastics, grease and oil. Due to the expense and time in removing such materials prior to open burning, the scrap is commonly left intact. The result is visible, toxic pollution and smoke as the materials burn off during open burning. Such discharges do not meet most environmental standards. On the other hand, if the combustibles are left on the scrap and processed in a mill, the gases released in the steel refining process will be highly flammable and problems develop with burning electrostatic precipitators and bag house filters.
Presently available systems for recycling obsolete scrap involve many isolated steps.
A large amount of obsolete scrap cannot be recycled by presently available systems because the cost of transporting the scrap to the recycling plant exceeds the value of the scrap as a No. 2 or No. 1 bundle. For this reason, thousands of tons of steel never reenter the steel production cycle. As the cost of energy increases, this problem becomes even more acute.
The composition of presently available scrap bundles is so poorly monitored that steel manufacturers must treat all bundles as a very low quality grade of iron. The highly fragmented nature of the obsolete scrap industry makes highly differentiated bundles presently unavailable.
Strict pollution control legislation has virtually eliminated the small scale smelter. The cost of air pollution control is excessive in terms of the value of the recycled metal produced.
Metal recycling systems have been developed that are capable of producing a high grade of scrap metal. However, the cost of these systems is very high and is far beyond the financial resources of many scrap processors. These recycling systems are fixed-site systems and are feasible only in large urban environments where large amounts of scrap are available. Collections of obsolete scrap in remote locations are not economically feasible. This extreme centralization of existing metal recycling systems, as well as the very low price of processed scrap in relationship to the value of processed metal, has led to decreased use of obsolete scrap in steel production.
Some existing systems recycle metals as a component of a municipal waste incinerator system. Because of the very high temperatures encountered in the incinerator, however, the steel fuses with copper and aluminum present in the waste, making the recycled metal virtually useless.
Electricity has been produced using heat recovery from incinerators. The electricity is either used on-site or sold to surrounding industries. The electricity generated has never been used to process the obsolete scrap recovered by the incinerator.
Many problems exist in the currently available systems for recycling obsolete scrap. A large amount of obsolete scrap is never recycled because of the short radius of operation of existing obsolete scrap recovery systems. Existing scrap recovery systems are heavy consumers of energy.
The demand for a system capable of recycling different metals in obsolete scrap on a single site with equipment that is capable of being moved from one scrap collection to another.